Polymerization catalyst systems comprising substituted hafinocenes

Abstract

The present invention relates to a process for the polymerization of monomers utilizing a bulky ligand hafnium transition metal metallocene-type catalyst compound, to the catalyst compound itself and to the catalyst compound in combination with an activator. The hafnocene comprises at least one cyclopentadienyl ligand including at least one linear or isoalkyl substituent of at least 3 carbon atoms.

We claim:  
     
       1. A process for polymerizing olefin(s) excluding cyclic olefin(s) in the presence of a catalyst system comprising a hafnium metallocene catalyst compound having at least one cyclopentadienyl or cyclopentadienyl derived ligand substituted with at least one linear or iso alkyl group having from 3 to 10 carbon atoms, and an activator. 
     
     
       2. The process in accordance with claim  1  where the linear or iso alkyl group has 3 to 5 carbon atoms. 
     
     
       3. The process in accordance with claim  1  wherein the ligand is one or more cyclopentadienyl ligands, wherein one of the cyclopentadienyl ligands is substituted with at least one linear or iso alkyl having 3 or 4 carbon atoms. 
     
     
       4. The process in accordance with claim  1  wherein the ligands are two cyclopentadienyl rings each substituted with at least one linear or iso alkyl group having 3 to 10 carbon atoms. 
     
     
       5. The process in accordance with claim  2  wherein the linear or iso alkyl group is selected from one or more of the group consisting of n-propyl, isopropyl, n-butyl, isobutyl and n-pentyl. 
     
     
       6. The process in accordance with claim  1  wherein the olefin(s) are alpha-olefins having from 2 to 12 carbon atoms. 
     
     
       7. The process in accordance with claim  1  wherein the olefin(s) are ethylene in combination with one or more other alpha-olefin(s) having from 3 to 10 carbon atoms. 
     
     
       8. The process in accordance with claim  1  wherein the process is a gas phase process. 
     
     
       9. The process in accordance with claim  1  wherein the catalyst system further comprises a support. 
     
     
       10. The process in accordance with claim  1  wherein the hafnium metallocene catalyst compound is bis(n-propyl-cyclopentadienyl) hafnium dichloride. 
     
     
       11. A continuous gas phase process for polymerizing olefin(s) excluding cyclic olefin(s) in a fluidized bed gas phase reactor in the presence of a catalyst system to produce a polymer product, the catalyst system comprising an activator and a hafnium metallocene catalyst compound having at least one cyclopentadienyl or cyclopentadienyl derived ligand substituted with at least one linear or iso alkyl group having from 3 to 10 carbon atoms, and the polymer product comprising less than 2 ppm hafnium. 
     
     
       12. The process of claim  11  wherein the polymer product comprises less than 1 ppm hafnium. 
     
     
       13. The process in accordance with claim  11  wherein the catalyst system is supported. 
     
     
       14. The process in accordance with claim  11  wherein the polymer product has a density greater than 0.915 g/cc. 
     
     
       15. The process in accordance with claim  11  wherein the olefin(s) are ethylene and at least one alpha-olefin(s) having 3 to 8 carbon atoms. 
     
     
       16. The process in accordance in accordance with claim  11  wherein the catalyst system is represented by the formula: 
       
         
           (C 5 H 5-d-f R″ d ) e R′″ f HfQ g-e    
         
       
       wherein (C 5 H 5-d-f R″ d ) is an unsubstituted or substituted cyclopentadienyl ligand bonded to Hf, wherein at least one (C 5 H 5-d-f R″ d ) is substituted with at least one R″ which is an alkyl group selected from the group consisting of n-propyl, isopropyl, isobutyl and n-pentyl, each additional R″, which can be the same or different is hydrogen or a substituted or unsubstituted hydrocarbyl having from 1 to 30 carbon atoms or combinations thereof or two or more carbon atoms are joined together to form a part of a substituted or unsubstituted ring or ring system having 4 to 30 carbon atoms, R′″ is one or more or a combination of the group consisting of carbon, germanium, silicon, phosphorous and nitrogen atoms containing radical bridging two (C 5 H 5-d-f R″ d ) rings, or bridging one (C 5 H 5-d-f R″ d ) ring to Hf; each Q which can be the same or different is selected from the group consisting of a hydride, substituted and unsubstituted hydrocarbyl having from 1 to 30 carbon atoms, halogen, alkoxides, aryloxides, amides, phosphides and combination thereof; two Q's together form an alkylidene ligand or cyclometallated hydrocarbyl ligand or other divalent anionic chelating ligand; where g is an integer corresponding to the formal oxidation state of Hf, d is 0, 1, 2, 3, 4, or 5, f is 0 or 1 and e is 1, 2, or 3, and the polymer product has a melt index less than 0.1 dg/min without the addition of hydrogen to the process. 
     
     
       17. A continuous slurry phase process for polymerizing olefin(s) excluding cyclic olefin(s) in the presence of a catalyst system to produce a polymer product in a liquid polymerization medium, the catalyst system comprising an activator and a hafnium metallocene catalyst compound having at least one cyclopentadienyl or cyclopentadienyl derived ligand substituted with at least one linear or iso alkyl group having from 3 to 10 carbon atoms, and the polymer product comprising less than 2 ppm hafnium. 
     
     
       18. The process in accordance with claim  17  wherein the polymer product comprises less than 1 ppm hafnium. 
     
     
       19. The process in accordance with claim  17  wherein the density is greater than 0.900 g/cc. 
     
     
       20. The process in accordance with claim  17  wherein the olefins are ethylene and at least one alpha-olefin(s) having 3 to 8 carbon atoms. 
     
     
       21. The process in accordance with claim  17  wherein the catalyst system is represented by the formula: 
       
         
           (C 5 H 5-d-f R″ d ) e R′″ f HfQ g-e    
         
       
       wherein (C 5 H 5-d-f R″ d ) is an unsubstituted or substituted cyclopentadienyl ligand bonded to Hf, wherein at least one (C 5 H 5-d-f R″ d ) is substituted with at least one R″ which is a linear or iso alkyl group having from 3 to 10 carbon atoms, each additional R″, which can be the same or different is hydrogen or a substituted or unsubstituted hydrocarbyl having from 1 to 30 carbon atoms or combinations thereof or two or more carbon atoms are joined together to form a part of a substituted or unsubstituted ring or ring system having 4 to 30 carbon atoms, R′″ is one or more or a combination of the group consisting of carbon, germanium, silicon, phosphorus and nitrogen atoms containing radical bridging two (C 5 H 5-d-f R″ d ) rings, or bridging one (C 5 H 5-d-f R″ d ) ring to Hf; each Q which can be the same or different is selected from the group consisting of hydride, substituted and unsubstituted hydrocarbyl having from 1 to 30 carbon atoms, halogen, alkoxides, aryloxides, amides, phosphides and combinations thereof; two Q's together form an alkylidene ligand or a cyclometallated hydrocarbyl ligand or other divalent anionic chelating ligand; where g is an integer corresponding to the formal oxidation state of Hf, d is 0, 1, 2, 3, 4 or 5, f is 0 or 1 and e is 1, 2 or 3, and the polymer product has a melt index less than 0.1 dg/min (ASTM D-1238-F or ASTM D-1238-E) without the addition of hydrogen to the process. 
     
     
       22. The process in accordance with claim  3  wherein the linear or iso alkyl group has 3 carbon atoms. 
     
     
       23. A process for polymerizing olefin(s) excluding cyclic olefin(s) in the presence of a catalyst system comprising a hafnium transition metal metalloccne catalyst having at least one cyclopentadienyl ring substituted with at least one alkyl group selected from group consisting of n-propyl, isopropyl, isobutyl and n-pentyl, and an activator. 
     
     
       24. A continuous gas phase process for polymerizing olefins excluding cyclic olefins in a fluidized bed gas phase reactor in the presence of a catalyst system to produce a polymer product, the catalyst system comprising an activator and a bulky ligand hafnium transition metal metallocene catalyst represented by the formula: 
       
         
           (C 5 H 5-d-f R″ d ) e R′″ f HfQ g-e    
         
       
       wherein (C 5 H 5-d-f R″ d ) is an unsubstituted or substituted cyclopentadienyl ligand bonded to Hf, wherein at least one (C 5 H 5-d-f R″ d ) is substituted with at least one R″ which is an alkyl group selected from the group consisting of n-propyl, isopropyl, isobutyl and n-pentyl, each additional R″, which can be the same or different is hydrogen or a substituted or unsubstituted hydrocarbyl having from 1 to 30 carbon atoms or combinations thereof or two or more carbon atoms are joined together to form a part of a substituted or unsubstituted ring or ring system having 4 to 30 carbon atoms, R′″ is one or more or a combination of the group consisting of carbon, germanium, silicon, phosphorus and nitrogen atoms containing radical bridging two (C 5 H 5-d-f R″ d ) rings, or bridging one (C 5 H 5-d-f R″ d ) ring to Hf; each Q which can be the same or different is selected from the group consisting of hydride, substituted and unsubstituted hydrocarbyl having from 1 to 30 carbon atoms, halogen, alkoxides, aryloxides, amides, phosphides and combinations thereof; two Q's together form an alkylidene ligand or cyclometallated hydrocarbyl ligand or other divalent anionic chelating ligand; where g is an integer corresponding to the formal oxidation state of Hf, d is 0, 1, 2, 3, 4 or 5, f is 0 or 1 and e is 1, 2 or 3, and the polymer product has a melt index less than 10 dg/min (ASTM D-1238-F or ASTM D-1238-E) without the addition of hydrogen to the process. 
     
     
       25. The process in accordance with claim  1  wherein the hafnium metallocene catalyst compound is a bis-cyclopentadienyl hafnium metallocene compound. 
     
     
       26. The process in accordance with claim  1  wherein the activator is alumoxane. 
     
     
       27. The process in accordance with claim  4  where in the linear or iso alkyl group has from 3 to 5 carbon atoms. 
     
     
       28. The process in accordance with claim  1  wherein the linear or iso alkyl group has 3 carbon atoms.